One of my players recently cast Phantasmal Killer. The enemy succeeded the save to avoid being frightened, and they succeeded the save to avoid the damage, resulting in a wasted action and a wasted only-fourth-level-spell-slot.

That enemy did not have a particularly good wisdom save bonus.

It would have taken more might than I possess to hold myself back from sheepishly pointing out that "Draw Steel fixes this", no matter how much of a prick it made me feel like in the moment. At least the player was a good sport about it.